Enhanced Sensitivity of Temperature Sensor with Transmitted Light of Fiber Bragg Grating

An optical temperature sensor utilizing transmitted light of fiber Bragg grating (FBG) is experimentally demonstrated in this work. For performance comparison, sensitivity of FBG transmitted light is compared with that of FBG reflected light. The measured sensitivity of transmitted light is 15.3 pm/°C, which is higher than 14.8 pm/°C recorded for the reflected light. Such enhanced sensitivity is influenced by the 3-dB bandwidth of the light signal. It is demonstrated that the transmitted light has narrower bandwidth of 0.12 nm rather than 0.23 nm for the reflected light and this factor contributes to enhanced sensitivity for the transmitted light.